DE102014004059A1 - vibration isolator - Google Patents

Abstract

Device for vibration isolation of buildings, which has a rolling body, which is located between an upper and lower bearing shell, the lower bearing shell is vertically sprung and mounted horizontally immovable, the rolling body is configured rotationally symmetrical, the rolling surfaces of the rolling body are formed with a radius of at least is as large as half the height of the rolling body and thereby has a spherical or lenticular shape, the rolling surfaces of the bearings are configured flat or rounded, and the vertical suspension of the lower bearing shell has a non-linear S-shaped curve.

Description

The invention relates to a vibration isolator for the protection of structures with the aim of intercepting earthquakes or other causes induced excitatory vibrations of the soil and thereby protect the structures from damage or even collapse.

The applications of the vibration isolator in buildings are diverse and span the entire area from traditional building construction to industrial and bridge construction. Even individual components of a building or machines and containers can be protected in this way.

Earthquakes are characterized by ground vibrations in both horizontal and vertical directions. The ratio of the horizontal to the vertical excitation component depends primarily on the position of the building to the epicenter and the so-called hearth depth of the earthquake. As a rule, the load caused by earthquakes in the horizontal direction is greater than in the vertical direction. In addition, as the distance to the epicenter increases, the size of the vertical exciter component falls faster than that of the horizontal exciter component. Therefore, seismic protection guidelines and common vibration isolation devices typically focus on horizontal earthquake excitation.

However, the vertical pathogen component in particular in the vicinity of epicentres takes on considerable orders of magnitude, which must be taken into account in the design of structures against earthquake loads.

• • Durch Federsysteme wird der Versuch unternommen, die Bodenerschütterungen abzufangen. Dabei werden in der Regel Stahl- oder Elastomerfedern verwendet.
• • Gleitlagersysteme ermöglichen dem aufgehenden Bauwerk über eine reibungsbehaftete Kontaktfläche auf dem Fundament zu gleiten.
• • Kinematischen Isolationssystemen liegen Wälzkörper zugrunde, die zwischen dem aufgehenden Bauwerk und dem Fundament platziert werden. Sie ermöglichen ein Abrollen des aufgehenden Bauwerks auf dem Fundament.

Basically, there is the need for isolation or damping systems to decouple the ground vibrations as possible from the movement of the rising structure. According to the relevant state of the art, various mechanisms are possible in principle for this purpose:

• • Spring systems attempt to intercept the ground vibrations. Usually steel or elastomeric springs are used.
• • Sliding bearing systems allow the rising structure to slide over a frictional contact surface on the foundation.
• • Kinematic insulation systems are based on rolling elements placed between the rising structure and the foundation. They allow rolling of the rising structure on the foundation.

Spring systems with steel springs are described in [ DE 102 33 023 B3 ], [ DE 30 40 181 A1 ] and [ DE 30 47 762 A1 ] presented. Steel spring elements generally have the disadvantage that they have little or no damping. The vibrations are slow to decay and, in cases where the excitation frequency is close to the natural frequency of the oscillatory system consisting of structure and springs, oscillations may occur.

Therefore, a high energy dissipation is often sought by damping or deformation effects in the material or in the damping element, such as in the spring systems with rubber and elastomeric bearings in [ DE 30 18 818 C2 ], [ DE 689 02 949 T2 ], [ DE 26 28 276 C2 ], [ DE 601 10 919 T2 ] and [ DE 33 05 850 A1 ].

Sliding bearings and sliding pendulum bearings are available in [ DE 10 2005 060 375 A1 ], [ DE 102 33 804 B3 ] and [EU 0 419 478 B1]. There, the rising building is connected to a sliding plate which is mounted horizontally movable on a shoe. The sliding block is mounted tiltable on the foundation. This system is primarily limited to the isolation of horizontal vibrations.

To make matters worse at friction and Gleitpendellagern such. In [ DE 10 2005 060 375 A1 ] added that they do not allow sufficient isolation due to the greater static friction compared to the smaller sliding friction in the initial state of the earthquake. Only when the excitation forces increase does the high static friction suddenly drop to the lower sliding friction, so that only then can the actual mechanical insulation begin. This start-up inhibition means that large parts of the earthquake excitation can not be isolated from the building.

Kinematic bearings of balls or rollers, or generally of specially shaped bodies, may provide a way to isolate horizontal earthquake excitation with little or no startup inhibition. Such systems are described in [ DE 299 14 460 U1 ], [ DE 199 53 891 A1 ], [ DE 10 2005 022 734 A1 ], [Demande de Brevet Europeen 0 143 052], [ DE 195 35 197 C1 ], [ DE 38 19 591 A1 ], [Offenlegungsschrift 2021 031].

In [ DE 199 53 891 A1 ] and [ DE 299 14 460 U1 ] balls are used, which are separated by spacers. However, this construction does not ensure that the structure returns to its original position after the excitement. As a result, the structure would be permanently misplaced.

In [ DE 10 2005 022 734 A1 ] and [Demande de Brevet Europeen 0 143 052] balls or cylindrical rollers are used, which are stored side by side in troughs. True, that is reversed to be isolated building after minor horizontal excitement back to its original position, however, there is no stop limit for major shocks. As a result, the balls or rollers could come to a stop in an adjacent trough, which would permanently misplaced the structure.

In [ DE 195 35 197 C1 ] balls are used, which are separated by spacers. A limitation for severe shocks is realized by a hard or almost hard stop, but this can lead to the fact that it can come by jerky impact load damage to building and / or bearing system.

In [ DE 38 19 591 A1 ] and [Offenlegungsschrift 2021 031] kinematic insulation systems are presented with specially shaped rolling elements, which form higher restoring forces at large deflections. Thus, the structure to be insulated returns to its original position after minor horizontal excitations. However, these systems either do not have a limit for heavy deflections or this limit is realized by a hard stop.

The previously mentioned systems are limited in that no vertical excitation components can be isolated or damped. Hybrid systems capable of absorbing both horizontal and vertical vibrations are described in [ U.S. Patent 4,517,778 ], [ WO 95/23267 ], [ DE 103 53 907 A1 ], [ DE 103 53 907 B4 ], [ JP 2003293611 A ] and [G 92 00 431.8].

In [ U.S. Patent 4,517,778 ] are used to isolate horizontal excitations balls as rolling elements, which are separated by spacers. The isolation of vertical excitations is achieved by an underlying system of parallel and / or serial coil springs.

In [ WO 95/23267 ] vibrations in the horizontal direction are intercepted by a system of cylindrical rollers and in the vertical direction by spring elements arranged underneath. Since the rollers are in troughs, the building to be insulated returns to its original position after completion of minor horizontal excitations. However, there is no stop limit for major shocks, so that the rollers could come to a halt in an adjacent trough. As a result, the structure would be permanently misplaced.

In [ DE 103 53 907 A1 and B4 ] a system is presented with a ball in a trough, which is spring-mounted in the vertical direction. This system characterized by the fact that low natural frequencies can be attenuated only in the range of 1.5 to 3.0 Hz. In fact, a variety of earthquake measurements shows that real excitation frequencies of up to 0.5 Hz can be significantly lower that can not be effectively isolated by the system. In addition, severe shocks are limited by hard stops in the form of Verspannmitteln, which can lead to the fact that it can come by jerky impact load damage to building and / or rolling bearing system.

In [G 92 00 431.8] a kinematic insulation system with specially shaped rolling elements is presented which form higher restoring forces for large deflections. Here, the spring system for receiving vertical excitations is no longer disposed below the rolling element, but integrated in the compressible rolling elements.

• • Die mechanische Isolation bzw. Dämpfung soll möglichst keine Anlaufhemmungen aufweisen.
• • Sie soll in der Gestalt so ausgebildet sein, dass das Bauwerk nach Ende des Erdbebens in die ursprüngliche Lage zurückkehrt.
• • Sie soll so ausgebildet sein, dass der Schwingungsisolator selbst bei starken Erregungen seine Funktionsfähigkeit beibehält.
• • Eine weitere Aufgabenstellung liegt darin, selbst niedrige Erregerfrequenzen von bis zu 0,5 Hz zu dämpfen.
• • Eine weitere Aufgabenstellung liegt in einer möglichst preiswerten und wartungsarmen Ausführung.

It is therefore an object to provide a vibration isolation device that mechanically isolates or attenuates a structure as well as possible in the case of horizontal as well as vertical excitation and thereby fulfills the following requirements:

• • The mechanical insulation or damping should as far as possible not exhibit any start-up inhibitions.
• • It should be designed in such a way that the building returns to its original position after the earthquake has ended.
• • It should be designed in such a way that the vibration isolator retains its functionality even in the case of strong excitation.
• • Another task is to attenuate even low excitation frequencies of up to 0.5 Hz.
• • Another task is a cheap as possible and low-maintenance execution.

• • einen Abrollkörper aufweist,
• • welcher sich zwischen einer oberen und unteren Lagerschale befindet,
• • die untere Lagerschale vertikal gefedert und horizontal unverschieblich gelagert wird,
• • dadurch gekennzeichnet, dass
• • der Abrollkörper rotationssymmetrisch ausgestaltet ist,
• • die Abrollflächen des Abrollkörpers mit einem Radius ausgebildet werden, der mindestens so groß ist wie die halbe Höhe des Abrollkörpers und dadurch eine ballige bzw. linsenförmige Form aufweist,
• • die Abrollflächen der Lagerschalen eben oder abgerundet ausgestaltet sind,
• • die vertikale Federung der unteren Lagerschale einen nichtlinearen S-förmigen Verlauf aufweist.

The vibration isolator according to the invention solves this problem, wherein the device

• Having a rolling body,
• • which is located between an upper and a lower bearing shell,
• The lower bearing shell is sprung vertically and stored horizontally,
• • characterized in that
• The rolling body is rotationally symmetrical,
• The rolling surfaces of the rolling body are formed with a radius that is at least as great as half the height of the rolling body and thus has a spherical or lenticular shape,
• The rolling surfaces of the bearing shells are flat or rounded,
• • The vertical suspension of the lower bearing shell has a non-linear S-shaped profile.

In one embodiment, it is provided that the rolling surfaces of the bearing shells are made flat in the central region and the upstand begins only outside the middle working range. As a result, small movements of the rolling body are little impeded and larger deflections are progressively reduced. This progressive reduction results from the fact that due to the upstand at larger deflections an increased increase of the structure takes place and thus a higher restoring force is generated.

A further embodiment relates to the arrangement of the vertical spring packs, which can also be designed so that the suspension can be done not only by a large spring assembly under the bearing shell, but also by a field of several, for example, 4, 9 or more adjacent spring packs.

A further embodiment relates to the spring element whose non-linear characteristic both by a special spring geometry, such. B. in disc springs, as well as by material with non-linear behavior, such as. B. in rubber or in particularly alloyed metals such. B. shape memory alloys (English Shape Memory Alloys), can be achieved.

A further embodiment relates to the rolling surfaces on the rolling body and the bearing shells, which can be performed by interlocking concentric grooves, which in the sectional view z. B. wavy or gear-like configured. This allows a deflection in any horizontal direction, without the rolling body in the bearing shell slides away horizontally or drifts away and then the rolling body no longer finds its exact starting position. A misplacement of the building is thus avoided.

The device of the invention will be explained with reference to 7 drawings, these drawings are only exemplary embodiments of the construction of the device according to the invention.

1 shows an exemplary arrangement of several vibration isolators under a building.

2 shows a schematic sectional view through the rolling body / rolling element at rest and in the deflected state.

3 shows an inventive isolation element with wave-shaped concentric grooves in the rolling surfaces and a disc spring package.

4 shows an inventive isolation element with gear-shaped concentric grooves in the rolling surfaces and a field of four cup spring packages.

5 shows an inventive isolation element with gear-shaped concentric grooves in the rolling surfaces and a spring construction of elastic material with non-linear material behavior.

6 shows an inventive insulation element, wherein the rolling surfaces are formed flat in the bearing shells in the central region and the upstand occurs only outside the central region. The vertical suspension is realized by a spiral spring with non-linear material behavior.

7 shows non-linear spring characteristics with and without hysteresis curve.

1 shows an exemplary arrangement of a plurality of vibration isolators 3 under a building 1 , The vibration isolators are placed between the foundation 4 and the bottom plate 2 of the building arranged. Ideally, there is an insulation element under each force introduction point, such as in the axis of a support of the structure. With sufficient rigidity of the bottom plate, however, the elements can also be arranged arbitrarily. The building sketched here is only an example of an arbitrary building. Likewise, it can be almost any type of structure such as a bridge or industrial plant or machine.

2 shows a schematic sectional view through the rolling body 5 at rest and in the deflected state. It can be seen that the radii of the rolling surfaces of the rolling body are formed greater than half the height of the rolling body; mathematically: r> h / 2. The rolling body thus corresponds to the middle part of a lens. This convex shape becomes the upper bearing shell 7 and thus the entire structure raised in the deflected state. As a result of this lifting caused by the weight of the structure a restoring force, which limits the deflection of the rolling body progressively and brings the rolling body back to its original position.

3 shows an inventive insulation element with a spherical rolling body 8th consisting of a central cylinder and two spherical caps between two bearing shells with wavy designed rolling surfaces 9 , The illustration shows the isolation element once in the idle state and once in the deflected state. By attaching the concentric grooves is in each arbitrary horizontal direction forced an ideal rolling and prevents horizontal drift, ie the rolling elements is always forced back into its original position. The lower bearing shell 10 is supported by a spring construction vertically displaceable but horizontally immovable. In this variant, the vertical suspension is through disc springs 11 achieved, which are particularly suitable by their non-linear design of the spring characteristic. The spring characteristic of disc springs is in the DIN 2092 described and shows with increasing deflection a degressive behavior, ie the spring is softer at the working point. In fact, as the vertical load increases further, solidification occurs again, which manifests itself in the spring characteristic in the form that it becomes steeper again beyond the working point (see 7 ). Hysteresis only occurs to a small extent, which is why the loading and unloading curves are almost identical.

4 , shows a variation of the vibration isolator, which is characterized in that the rolling surfaces 12 on rolling body and bearing shells not wavy, but are gear-shaped. In the variant shown here, under the lower bearing shell is a field of four spring assemblies 13 educated.

5 , shows a variation of the vibration isolator, which is characterized in that the vertical suspension by a non-linear material 14 (eg, elastomers, shape memory alloys) is formed. Thus, such materials have a force curve in the form of a hysteresis, which is characterized by different curves during loading and unloading (see 7 ). The hysteresis assumes the essential part of the damping, which is characterized by the area integral between loading and unloading curve.

6 shows an inventive isolation element with wave-shaped concentric grooves in the rolling surfaces. The rolling surfaces 15 in the bearing shells are flat here in the middle area. The bulge occurs only outside the middle work area, so that with smaller deflections a moderate restoring force arises. For larger deflections a strong Aufkantungseffekt, whereby the structure is raised progressively and thus a high restoring force is formed. In the embodiment shown here are spiral springs 16 used with nonlinear material behavior.

7 , shows both a nonlinear spring characteristic 17 a spring construction consisting of z. B. from disc springs as well as a non-linear spring characteristic 18 a spring packet consisting of z. B. from a pseudoelastic shape memory alloy with nonlinear material behavior. Here is in particular the hysteresis-shaped course 18 to recognize between loading and unloading.

LIST OF REFERENCE NUMBERS

1

building

2

Base plate of the rising structure

3

vibration isolator

4

foundation pit

5

unwinding

6

Level of the lower bearing shell

7

Level of the upper bearing shell

8th

unwinding

9

Rolling surfaces with wavy profile

10

Lower bearing shell (vertically displaceable, horizontally non-displaceable)

11

Spring package with disc springs

12

Rolling surfaces with gear-shaped profile

13

Field with four spring packages

14

Spring element made of special material with non-linear material behavior

15

Rolling surface with straight central part and curved edge

16

Spiral springs with nonlinear material behavior

17

Nonlinear spring characteristic without hysteresis

18

Nonlinear spring characteristic with hysteresis

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 10233023 B3 [0006]
• DE 3040181 A1 [0006]
• DE 3047762 A1 [0006]
• DE 3018818 C2 [0007]
• DE 68902949 T2 [0007]
• DE 2628276 C2 [0007]
• DE 60110919 T2 [0007]
• DE 3305850 A1 [0007]
• DE 102005060375 A1 [0008, 0009]
• DE 10233804 B3 [0008]
• DE 29914460 U1 [0010, 0011]
• DE 19953891 A1 [0010, 0011]
• DE 102005022734 A1 [0010, 0012]
• DE 19535197 C1 [0010, 0013]
• DE 3819591 A1 [0010, 0014]
• US 4517778 [0015, 0016]
• WO 95/23267 [0015, 0017]
• DE 10353907 A1 [0015, 0018]
• DE 10353907 B4 [0015, 0018]
• JP 2003293611 A [0015]

Cited non-patent literature

• DIN 2092 [0036]

Claims (5)

Device for vibration isolation of structures, • which has a rolling body, • which is located between an upper and lower bearing shell, • the lower bearing shell is vertically sprung and horizontally mounted immovably, characterized in that • the rolling body is configured rotationally symmetrical, • the rolling surfaces of the Abrollkörpers are formed with a radius which is at least as large as half the height of the rolling body and thereby has a spherical or lenticular shape, • the rolling surfaces of the bearing shells are designed even or rounded, • the vertical suspension of the lower bearing shell a nonlinear S has a shaped course. Apparatus according to claim 1, characterized in that the rolling surfaces of the bearing shells are made flat in the central region and the upstand only begins outside the middle working range. Apparatus according to claim 1 to 2, characterized in that the suspension is effected not only by a large spring assembly under the bearing shell, but also by a field of several juxtaposed spring assemblies. Apparatus according to claim 1 to 3, characterized in that the non-linear characteristic of the spring element is realized both by a special spring geometry and by material with non-linear behavior. Apparatus according to claim 1 to 4, characterized in that the rolling surfaces are performed on the rolling body and the bearing shells by interlocking concentric grooves.

Images